'O Canada': the first text message sent using alcohol

"O Canada", the title of the Canadian national anthem, is the first text message to have been sent using an inexpensive alcohol-based chemical messaging system.

A chemical signal with different levels of concentration of rubbing alcohol (to communicate different letters) was sent four metres across the lab with the aid of a tabletop fan. It was then decoded by a receiver and turned back into a text message.

The programmable platform performs molecular communication, which mimics chemical signalling found in nature. The best known example of this is pheromone signalling used by social insects such as ants for long-range communications. Chemical signals are also used in inter-cellular and intra-cellular communication. This approach to communications can be advantageous for situations when electromagnetic wireless systems are inefficient, for example in networks of tunnels, underwater, or at very small scales when antenna size is restricted.

All communication systems rely on three major elements: the transmitter, the receiver and the channel. The transmitter takes an input text message from the user and converts it into a sequence of binary bits.

The research team -- from Toronto's York University and the UK's Warwick University -- used the Arduino Uno electronics prototyping platform, using a 16x2 character LCD Shield Kit -- an add-on module with six push buttons -- for text entry. The text was then converted into a binary sequence (each letter was represented using five bits according to the International Telegraph Alphabet No.2, so the letter E is represented by 10000) and modulated into chemical signals (where a spray represented 1 and no spray represented 0) using an electronic spray mechanism called DuroBlast, which was controlled by an Arduino micro controller.

The receiver had to be a sensor that could detect a chemical signal, which can then be processed and decoded back into text. Again, the team used the Arduino Uno micro controller to read the sensor data, decode it and then display a text message on a computer screen.

Wired.co.uk: Alcohol-based SMS transmission of 'O Canada'Wired UK

The team used isopropyl alcohol (rubbing alcohol) as the signalling chemical, since it is widely available, volatile, inexpensive and there are a number of cheap sensors available to detect it. However, the receiver could also work with ethanol.

The message could be transmitted four metres using a Honeywell desktop fan positioned behind the spray device. The team found that a Dyson fan could create a better system response, but they were trying to keep the costs of the system as low as possible.

The researchers tried various transmission rates, from one bit per five seconds (a character every 25 seconds) to one bit per 2 seconds (a character every 10 seconds) across distances between one metre and four metres. The system was deemed to be "very reliable" at the slowest rate across all distances and very unreliable at the highest rate.

"We believe we have sent the world's first text message to be transmitted entirely with molecular communication, controlling concentration levels of the alcohol molecules, to encode the alphabets with single spray representing bit 1 and no spray representing the bit 0," said doctoral candidate Nariman Farsad, from York University in a press release.

Engineering Professor Weisi Guo from the University of Warwick added that the system could be used to communicate on the nanoscale, "for example in medicine where recent advances mean it's possible to embed sensors into the organs of the body or create miniature robots to carry out a specific task such as targeting drugs to cancer cells."